_Throat_, the opening or gorge of a monopetalous corolla, &c., where the border and the tube join, and a little below, 89. _Thyrse_ or _Thyrsus_, a compact and pyramidal panicle of cymes or cymules, 79. _Tomentose_, clothed with matted woolly hairs (_tomentum_). _Tongue-shaped_, long and flat, but thickish and blunt. _Toothed_, furnished with teeth or short projections of any sort on the margin; used especially when these are sharp, like saw-teeth, and do not point forwards, 55. _Top-shaped_, shaped like a top, or a cone with apex downwards. _Torose_, _Torulose_, knobby; where a cylindrical body is swollen at intervals. _Torus_, the receptacle of the flower, 81, 112. _Trachea_, a spiral duct. _Trachys_, Greek for rough; used in compounds, as, _Trachyspermous_, rough-seeded. _Transverse_, across, standing right and left instead of fore and aft. _Tri-_ (in composition), three; as, _Triadelphous_, stamens united by their filaments into three bundles, 99. _Triandrous_, where the flower has three stamens, 112. _Tribe_, 178. _Trichome_, of the nature of hair or pubescence. _Trichotomous_, three-forked. _Tricoccous_, of three cocci or roundish carpels. _Tricolor_, having three colors. _Tricostate_, having three ribs. _Tricuspidate_, three-pointed. _Tridentate_, three-toothed. _Triennial_, lasting for three years. _Trifarious_, in three vertical rows; looking three ways. _Trifid_, three-cleft, 56. _Trifoliate_, three-leaved. _Trifoliolate_, of three leaflets. _Trifurcate_, three-forked. _Trigonous_, three-angled, or triangular. _Trigynous_, with three pistils or styles, 116. _Trijugate_, in three pairs (_jugi_). _Trilobed_ or _Trilobate_, three-lobed, 55. _Trilocular_, three-celled, as the pistils or pods in fig. 328-330. _Trimerous_, with its parts in threes. _Trimorphism_, 117. _Trimorphic_ or _Trimorphous_, in three forms. _Trinervate_, three-nerved, or with three slender ribs. _Triœcious_, where there are three sorts of flowers on the same or different individuals, as in Red Maple. A form of Polygamous. _Tripartible_, separable into three pieces. _Tripartite_, three-parted, 55. _Tripetalous_, having three petals. _Triphyllous_, three-leaved; composed of three pieces. _Tripinnate_, thrice pinnate, 59. _Tripinnatifid_, thrice pinnately cleft, 57. _Triple-ribbed_, _Triple-nerved_, &c., where a midrib branches into three, near the base of the leaf. _Triquetrous_, sharply three-angled; and especially with the sides concave, like a bayonet. _Triserial_, or _Triseriate_, in three rows, under each other. _Tristichous_, in three longitudinal or perpendicular ranks. _Tristigmatic_, or _Tristigmatose_, having three stigmas. _Trisulcate_, three-grooved. _Triternate_, three times ternate, 59. _Trivial Name_, the specific name. _Trochlear_, pulley-shaped. _Trumpet-shaped_, tubular; enlarged at or towards the summit. _Truncate_, as if cut off at the top. _Trunk_, the main stem or general body of a stem or tree.